There are two types of people in this world: The kind who kill houseplants and the kind who do not. If you're the former, mull over these shopping tips from Vicki Prosek of Florist-At-Large at the San Francisco Flower Mart before choosing for your next potted victim.

- Bromeliad: Prosek refers to this as the "bachelor" houseplant, which ought to give you an idea instantly about its patience with owners who do not have green thumbs. This tropical plant has a series of cup-shaped leaves that extend into the next. And its bright, spiffy blossom structure remains even after it's finished blooming. Since the plant's native habitat is cloud forest, it does well in humid spots like bathroom windowsills. Water once a week.

- Grafted euphorbia: For a particularly warm, sunny window, try a grafted euphorbia. The plant has a spiked tubular trunk that's topped with wavy spoon-shaped leaves. Let the soil dry between waterings and check it occasionally to ensure it's well drained.

- Pothos: This leafy, versatile houseplant can endure two of the biggest plant maintenance no-nos for extended periods of time: Low light and low water levels.

- Spath: This hardy, leafy dark green plant has long skinny stems with a spike of itsy-bitsy white micro flower at its tips. It thrives in low light and it actually hangs onto water for weeks before drooping leaves signal that it's time for a swig.

- Buy some plant insurance: If your green roommates are dropping like flies, consider purchasing a water-measuring gadget like the EasyBloom Plant Sensor ($60). This handheld device can determine where plants will work best in your dwelling and can even diagnosis ailing plants (easybloom.com).